Existing mobile devices such as cellular telephones or personal digital assistants (PDA) have global positioning system (GPS) capabilities. These mobile devices typically include computer-readable media storing navigational map information such as, for example, road information, address information, and the like. Existing mobile devices download a partial or an entire geographic region to provide a user with detailed map and routing information. However, the mobile devices typically have limited storage capacity that is often exclusively dedicated to map regions, thus leaving limited functionality for navigation purposes. Example navigation purposes include accessing real-time information such as traffic congestion or local advertising. Further, there are often costs passed along to an end user when manually updating the map regions.
Some mobile devices include network connections and mobile operator application services for providing location-based map services. These mobile devices have the ability to download map tiles on demand and to retain a local cache of recently traveled regions for future access. To keep memory use to a minimum, however, these existing systems do not account for moments of intermittent loss of network connectivity or for geographic regions without signal coverage. Further, retained map tiles are purged as soon as the corresponding portion of the route has been traversed. Upon entering an area of poor network connectivity or no signal coverage, map tiles are either intermittently received and displayed, or not received or displayed at all.